2019-02-22T13:44:06Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/51982016-02-16T02:57:13Zcom_10261_39com_10261_1col_10261_292DIGITAL.CSICauthorNúñez, Lucía2008-06-20T07:23:35Z2007-04-15Journal of Physiology 580(2): 385–395 (2007)0022-3751http://hdl.handle.net/10261/519810.1113/jphysiol.2006.126524Changes in the cytosolic Ca2+ concentration ([Ca2+]c) are essential for triggering neurotransmitter release from presynaptic nerve terminals. Calcium-induced Ca2+ release (CICR) from the endoplasmic reticulum (ER) may amplify the [Ca2+]c signals and facilitate neurotransmitter release in sympathetic neurons. In adrenal chromaffin cells, functional triads are formed by voltage-operated Ca2+ channels (VOCCs), CICR sites and mitochondria. In fact, mitochondria take up most of the Ca2+ load entering the cells and are essential for shaping [Ca2+]c signals and exocytosis. Here we have investigated the existence of such functional triads in sympathetic neurons. The mitochondrial Ca2+ concentration ([Ca2+]m) in soma and neurites of individual mouse superior cervical ganglion (SCG) neurons was monitored by bioluminescence imaging of targeted aequorins. In soma, Ca2+ entry through VOCCs evoked rapid, near millimolar [Ca2+]m increases in a subpopulation of mitochondria containing about 40% of the aequorin. Caffeine evoked a similar [Ca2+]m increase in a mitochondrial pool containing about 30% of the aequorin and overlapping with the VOCC-sensitive pool. These observations suggest the existence of functional triads similar to the ones described in chromaffin cells. In neurites, mitochondria were able to buffer [Ca2+]c increases resulting from activation of VOCCs but not those mediated by caffeine-induced Ca2+ release from the ER. The weaker Ca2+ buffering by mitochondria in neurites could contribute to facilitate Ca2+-induced exocytosis at the presynaptic sites.engclosedAccessBioluminescence imaging of mitochondrial Ca2+ dynamics in soma and neurites of individual adult mouse sympathetic neuronsArtí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URLhttps://digital.csic.es/bitstream/10261/5198/3/accesoRestringido.pdfFileMD542637ae8545636bc41605c1740a9a84e15753application/pdfaccesoRestringido.pdfURLhttps://digital.csic.es/bitstream/10261/5198/5/accesoRestringido.pdf.txtFileMD57c821e3180e847b607957fd9795236ad401text/plainaccesoRestringido.pdf.txt